• Asian Journal of Turfgrass Science
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• v.5 no.1
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• pp.23-32
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• 1991

The purpose of this study was to determine the vegetative growth of two cool season turfgrasses during summer season in Korea. Ten respective cultivars of Kentucky bluegrass [Poapratensis L.] and perennial ryegrass [Lolium perenne L.] were exposed to unshaded, 30% and 60% shade for 4odays. First mowing height was 7cm, and then clippings were harvested every ten days at the same height. Shading increased the total length of clippings of all cultivars of two turfgrasses, but fresh and dry weight were significantly decreased. The highest shoot length obtained at 30% shade in Kentucky bluegrass and at 60% shade in perennial ryegrass. 'Rugky', 'Sydsport', 'Wabash' and 'Baron' of Kentucky bluegrass and 'Repel', 'Omega II', 'Ovation', 'Linn', 'Bell' and 'Manhattan' of perennial ryegrass showed relatively high tolerance to shade. Especially, in 'Citation II' perennial ryegrass, fresh and dry weight were increased by 30% shade. The number of tillers generally decreased with increasing shade. In 30% shade, 'Midnight' Kentucky bluegrass and 'Omega II' perennial ryegrass were least reduced and 'Baron' Kentucky bluegrass and 'Pennant' perennial ryegrass were most reduced. The cultivars of lower growth habit in full sunlight showed shade tolerance compared to those of higher growth habit.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.680-689
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• 2008

This present study was conducted to investigate photosynthetic responses and chlorophyll fluorescence performances of Cornus controversa, Fraxinus rhynchophylla, Betula schmidtii, Prunus leveilleana, and Acer mono seedlings growing under four different light intensity regimes (full sun, and 65~72%, 29~40%, 7~12% of full sun). As result, Cornus controversa, Fraxinus rhynchophylla, and Betula schmidtii showed outstanding photosynthetic capacities in full sun and showed low shade tolerance. Prunus leveilleana showed good photosynthetic capacity in three treatment levels except for 7~12% of full sun and showed common shade tolerance. While, Acer mono showed good photosynthetic capacity and chlorophyll fluorescence in 29~40% of full sun. Acer mono showed the highest shade tolerance compared to the other four species.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.292-298
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• 1999

Huber value and leaf specific conductivity were investigated for determining the hydraulic conductance of six deciduous hardwood species subjected to five levels of artificial shade treatments. Huber values measured in full sun were in the ranges of $1.5{\sim}9.1mm^2/dm^2$, $1.3{\sim}2.6mm^2/dm^2$, $1.5{\sim}5.3mm^2/dm^2$ in June, July, and September, respectively in the first year. The values generally decreased with increasing the shading in most of the species studied. Because of early defoliation in September, most of the values measured were also higher in September than in July. Huber values were quite different between those of the first year and those of the second year in most of the species studied, but the seasonal variation of Huber values and shading effects to the values seemed to be similar between the first and the second years. The values of leaf specific conductivity(LSC) measured in Betula platyphylla var. japonica. B. schmidtii, Zelkova serrata, Acer mono for 2 years were in the range of $4.0{\sim}80.0{\mu}{\ell}/dm^2$ by season and by shading treatment. But in Ligustrum obtusifolium and Prunus sargentii, the values were in the ranges of $4.0{\sim}280.0{\mu}{\ell}/dm^2$ and $8.0{\sim}120{\mu}{\ell}/dm^2$, respectively with having quite different values compared with those of the above species. Seasonal variation of LSC values was more or less irregular by species and by treatment year, but the LSC values of B. platyphylla vac. japonica, B. schmidtii, and P. sargentii in the first year and also those of Z. serrata and P. sargentii in the second year were mostly higher in September than in July. The LSC values seemed to be generally decreased with increasing the artificial shading in all of the species studied.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.36-48
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• 2010

This present study was conducted to investigate photosynthetic characteristics, chlorophyll fluorescence, chlorophyll contents of Betula platyphylla var. japonica, Prunus leveilleana, Magnolia sieboldii, growing under four different light intensity regimes (full sun, and 64~73%, 35~42%, 9~16% of full sun). As result, Betula platyphylla var. japonica showed outstanding photosynthetic capacity and apparent quantum yield in full sun and showed low shade tolerance. Prunus leveilleana showed good photosynthetic capacity and apparent quantum yield in 64~73% or 35~42% of full sun and showed common shade tolerance. However, Magnolia sieboldii showed good photosynthetic capacity and apparent quantum yield in 35~42% of full sun, while the lowest in full sun. Magnolia sieboldii showed the highest shade tolerance compared to the other species. As the shading level increased, the total chlorophyll contents of all species increased with significant difference.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.103-108
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• 1998

The Canadian production of American ginseng (Panax quinquefolius L.) occurs mainly in Ontario, British Columbia and the Atlantic provinces. Although ginseng is a profitable crop, its successful production is dependent on careful consideration of cultural management f include site selection, site preparation, seed selection and handling, shading actors which and mulching, pest and nutritional management, and handling of harvested crops. Diseases of particular concern in Atlantic Canada are root rots caused by Phytopkthora cactorum, Cylindrocarpon destructans and Fusarium sp. Recently two systemic fungicides (metalaxyl and fosetylal) were registered; however, growers in Atlantic Canada have experienced metalaxyl resistance resulting from the reliance on this single compound for the control of Phytophthora sap. Current research being conducted on alternative control of these diseases will be discussed. In weed control research, 2, 4-D, MCPA, clopyralid have continued to show promise for weed contro1 at low rates. In trials to evaluate non-selective herbicides as post-senescence or pre-emergence in ginseng, glyphosate (Round-up) provided control of perennials as well as willowherb and lambsquarters. In phytoxicity trials, ginseng significantly tolerated grass herbicides, including clethodim, rimsulfuron, trakloxydim, nicosulfuron and fenoxyprop. For broadleaf herbicides, significant tolerance was shown for bromoxynil, thifensulfuron methyl, flumetulam/clopyralid, thifensulfuro/tribenuron. Disease and weed management of ginseng in Atlantic Canada will be discussed.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.2
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• pp.68-75
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• 2017

Demand for dwarf mondo grass (DMG; Ophiopogon japonicus 'Nanus') as an ornamental garden plant is expected to grow in the future. The purpose of this study was to investigate the levels of shade tolerance and ground cover by growing DMG under a variety of shade conditions for 18 months (May 2015~October 2016). DMG plants grown in bare ground for 3 years in Jangheung-gun, Jeonnam were used for testing. In an experimental site created in Naju city in Jeonnam, the DMG was planted in planters ($70cm{\times}70cm{\times}24cm$) and covered with a shading curtain to block natural light. Shaded conditions were then arranged under different levels of shade (0%, 55% and 75%). When the plants were grown, growth (leaf size, the number of leaves, fresh weight and dry weight) and ground coverage of DMG were analyzed. According to the results, DMG growth in terms of leaf size and the number of leaves was statistically higher under zero shade (full sunlight), when compared to other shaded conditions. DMG's fresh and dry weights were significantly greater under 0% and 55% shade, compared to those under 75% shade. The degrees of shade tolerance required for normal growth of DMG were found in the range of 0~50%, meaning that more than 50% shade may decrease plant growth. There were no statistical differences in ground coverage rates of DMG under different levels of shade. When 220 tillers were planted per $1m^2$ of plot, up to 80% of the area was covered by DMG after 18 months. Since DMG requires nutrient-rich soil to grow, sufficient nitrogen fertilizers are proposed to accelerate the ground cover of DMG. As DMG remained alive over the winter in the experiments, this study also suggests that DMG can be planted in the southern temperate region.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1101-1107
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• 2022

The leaf temperature is principally regulated by the opening and closing of stomata that is sensitive to various kinds of plant physiological stress. Thus, the analysis of thermal imagery, one of remote sensing technique, will be useful to detect crop physiological condition on smart farm system and phenomics platform. However, there are few case studies using a thermal imaging camera on the agricultural application. In this study, three cases are presented: the effect of lime fertilizer on the rice, the different physiological properties of soybean under shading condition, and the screening of soybean breeds for salinity tolerance characteristic. The leaf temperature measured by thermal imaging camera on the three cases was used effectively to the physiological change and characteristics. However, the thermal imagery analysis requires considering the accuracy of measured temperature and the weather conditions that affects to the leaf temperature.

• Journal of Korean Society of Forest Science
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• v.96 no.4
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• pp.462-469
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• 2007

The present study was conducted to investigate photosynthetic responses and growth performances of Liriodendron tulipifera, Betula costata, and Carpinus cordata seedlings growing under four different light regimes (full sun and 54~65%, 26~37%, 8~13% of full sun). L. tulipifera and B. costata showed the highest photosynthesis rate of 13.59, $16.29{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$, respectively, at full sun. And photosynthesis ability and growth performances were decreased as increasing shade level in the above two species. C. cordata showed the highest photosynthesis rate of $9.47{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ at 26~37% of full sun. Also, growth performances of height, root collar diameter, and biomass showed the results similar to photosynthetic responses presented in C. cordata.

• Journal of Biosystems Engineering
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• v.25 no.3
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• pp.213-220
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• 2000

Grafting of fruit-bearing vegetables has been widely used to increase the resistance to soil-borne diseases, to increase the tolerance to low temperature or to soil salinity, to increase the plant vigor, and to extend the duration of economic harvest time. After grafting, it is important to control the environment around grafted seedlings for the robust joining of a scion and rootstock. Usually the shading materials and plastic films are used to keep the high relative humidity and low light intensity in greenhouse or tunnel. It is quite difficult to optimally control the environment for healing and acclimation of grafted seedlings under natural light. So the farmers or growers rely on their experience for the production of grafted seedling with high quality. If artificial light is used as a lighting source for graft-taking of grafted seedlings, the light intensity and photoperiod can be easily controlled. The purpose of this study was to develop a prototype system for the graft-taking enhancement of grafted seedlings using artificial lighting and to investigate the effect of air current speed on the distribution of air temperature and relative humidity in a graft-taking enhancement system. A prototype graft-taking system was consisted by polyurethane panels, air-conditioning unit, system controller and lighting unit. Three band fluorescent lamps (FL20SEX-D/18, Kumho Electric, Inc.) were used as a lighting source. Anemometer (Climomaster 6521, KANOMAX), T-type thermocouples and humidity sensors (CHS-UPS, TDK) were used to measure the air current speed, air temperature and relative humidity in a graft-taking system. In this system, air flow acted as a driving force for the diffusion of heat and water vapor. Air current speed, air temperature and relative humidity controlled by a programmable logic controller (UP750, Yokogawa Electric Co) and an inverter (MOSCON-G3, SAMSUNG) had an even distribution. Distribution of air temperature and relative humidity in a graft-taking enhancement system was fairly affected by air current speed. Air current speed higher than 0.1m/s was required to obtain the even distribution of environmental factors in this system. At low air current speed of 0.1m/s, the evapotranspiration rate of grafted seedlings would be suppressed and thus graft-taking would be enhanced. This system could be used to investigate the effects of air temperature, relative humidity, air current speed and light intensity on the evaportranspiration rate of grafted seedlings.